1. Field of the Invention
The present invention relates to a resin material that lessens the burden on the global environment. The present invention also relates to a method of recycling the resin composition for material circulation to build a recycling society.
2. Related Background Art
Mankind has successively created various materials useful in daily lives and in industries through the coal chemistry age and the petroleum chemistry age. In particular, the symbolic examples of these materials are synthetic polymer resins, which include plastic materials, such as polyethylene, polypropylene, and polyvinyl chloride; and rubbers such as polyisoprene, and polybutadiene. Recently, novel resin materials having excellent properties have been developed, including polyimide resins and all-aromatic liquid crystalline polymers having high heat resistance and high impact strength.
In recent years, however, in the industrial structure based on mass production, mass consumption, and mass waste, discarded polymers have caused a number of problems. Specifically, the discarded materially stable polymer materials remain undecomposed in the soil for a long time, gradually releasing endocrine disruptors and other harmful substances that occasionally have serious adverse effects on living organisms. When the polymer materials are incinerated, toxic materials, such as dioxin, can be generated depending on the incineration conditions, causing an extreme danger. Another waste material that causes environmental problems is waste paper, a large amount of which is discharged from offices.
Under such circumstances, materials and products that do not destroy the environment are wanted. Further, technical developments are required that enable conservation of the environment by minimizing the consumption of global resources and by recycling the materials.
On the other hand, one of the general methods for improving the properties of the polymer is an introduction of a fiber structure into a polymer by blending a foreign material. Generally, this method includes blending an inorganic material, such as a glass fiber, and a carbon fiber; blending an organic polymer fiber, such as a nylon fiber, and a polyester fiber; and blending a liquid crystalline polymer having high orientability. For example, U.S. Pat. No. 6,248,267 discloses a natural-fiber-containing nonwoven fabric. Lately, the amounts of industrial waste materials and household waste materials are increasing, and the disposed materials are causing a social problem. Generally, organic polymer materials, such as polyethylene and polypropylene are stable, and once discarded, they will persist in the soil for a long time. To avoid such a problem, the use of a biodegradable polymer materials is considered. However, biodegradable polymers do not have satisfactory properties in the broad range of application fields in comparison with the versatile polymer materials. The properties of a biodegradable polymer can be improved by blending the aforementioned fiber material. However, the blended filler, which is not biodegradable, makes recycling difficult, resulting in an increased burden on the environmental by remaining undecomposed for a long time after disposal.